Returns TRUE if all the arguments are considered TRUE, and FALSE otherwise.
AND(argument1; argument2 ...argument30)
argument1 to argument30 are up to 30 arguments, each of which may be a logical result or value, or a reference to a cell or range.
AND tests every value (as an argument, or in each referenced cell), and returns TRUE if they are all TRUE. Any value which is a non-zero number or text is considered to be TRUE.
If cells A5:B8 all contain TRUE, cell C2 contains =TRUE() and cell C3 contains "dog":